Washington County Water Quality: 3 Cities Ranked by the Records
Washington County, Wisconsin: 3 city reports built from EPA and utility records. A county has many suppliers; each city shows the system that serves it.
Highest result for each contaminant
One row per contaminant: the highest result any system in the county reported, against its limit. Open a row for the systems behind it.
LithiumDetected in 1 system of 3 tested10 µg/L EPA health reference level (screening, not a legal limit) · US EPAHighest30 µg/L
- GERMANTOWN WATER UTILITY30 µg/LSample date: 2023-09-19 to 2024-02-22
- HARTFORD WATERWORKSNot detected · below 9.0 µg/L lab reporting limitSample date: 2024-02-19 to 2024-08-26
- WEST BEND WATERWORKSNot detected · below 9.0 µg/L lab reporting limitSample date: 2025-06-17 to 2025-12-03
Perfluorooctanoic acid (PFOA)Detected in 2 systems of 3 tested4.0 ng/L federal MCL (2024) · US EPAHighest6.8 ng/L
- HARTFORD WATERWORKS6.8 ng/LSample date: 2024-02-19 to 2024-08-26
- WEST BEND WATERWORKS6.5 ng/LSample date: 2025-06-17 to 2025-12-03
- GERMANTOWN WATER UTILITYNot detected · below 4.0 ng/L lab reporting limitSample date: 2023-09-19 to 2024-02-13
Perfluorooctanesulfonic acid (PFOS)Detected in 1 system of 3 tested4.0 ng/L federal MCL (2024) · US EPAHighest5.5 ng/L
- HARTFORD WATERWORKS5.5 ng/LSample date: 2024-02-19 to 2024-08-26
- GERMANTOWN WATER UTILITYNot detected · below 4.0 ng/L lab reporting limitSample date: 2023-09-19 to 2024-02-13
- WEST BEND WATERWORKSNot detected · below 4.0 ng/L lab reporting limitSample date: 2025-06-17 to 2025-12-03
Perfluorohexanesulfonic acid (PFHxS)Detected in 1 system of 3 tested10 ng/L federal MCL (2024) · US EPAHighest6.1 ng/L
- HARTFORD WATERWORKS6.1 ng/LSample date: 2024-02-19 to 2024-08-26
- GERMANTOWN WATER UTILITYNot detected · below 3.0 ng/L lab reporting limitSample date: 2023-09-19 to 2024-02-13
- WEST BEND WATERWORKSNot detected · below 3.0 ng/L lab reporting limitSample date: 2025-06-17 to 2025-12-03
Lead (90th percentile)Detected in 3 systems15 µg/L federal action level · US EPAHighest5.8 µg/L
- WEST BEND WATERWORKS5.8 µg/LMonitoring period: 2026–2026 (still open)
- GERMANTOWN WATER UTILITY1.7 µg/LMonitoring period: 2023–2023
- HARTFORD WATERWORKS0.86 µg/LMonitoring period: 2023–2023
Perfluorobutanesulfonic acid (PFBS)Detected in 2 systems of 3 tested2,000 ng/L EPA health advisory (screening, not a legal limit) · US EPAHighest3.9 ng/L
- WEST BEND WATERWORKS3.9 ng/LSample date: 2025-06-17 to 2025-12-03
- HARTFORD WATERWORKS3.2 ng/LSample date: 2024-02-19 to 2024-08-26
- GERMANTOWN WATER UTILITYNot detected · below 3.0 ng/L lab reporting limitSample date: 2023-09-19 to 2024-02-13
25 PFAS tested, none detected in any systemShow
Tested in these 3 systems: GERMANTOWN WATER UTILITY, HARTFORD WATERWORKS, WEST BEND WATERWORKS
- 11-Chloroeicosafluoro-3-oxaundecane-1-sulfonic acid (11Cl-PF3OUdS)
- 1H, 1H, 2H, 2H-perfluorodecane sulfonic acid (8:2 FTS)
- 1H, 1H, 2H, 2H-perfluorohexane sulfonic acid (4:2 FTS)
- 1H, 1H, 2H, 2H-perfluorooctane sulfonic acid (6:2 FTS)
- 4,8-Dioxa-3H-perfluorononanoic acid (ADONA)
- 9-Chlorohexadecafluoro-3-oxanone-1-sulfonic acid (9Cl-PF3ONS)
- Hexafluoropropylene oxide dimer acid (HFPO-DA) (GenX chemicals)
- N-ethyl perfluorooctanesulfonamidoacetic acid (NEtFOSAA)
- N-methyl perfluorooctanesulfonamidoacetic acid (NMeFOSAA)
- Nonafluoro-3,6-dioxaheptanoic acid (NFDHA)
- Perfluoro (2-ethoxyethane) sulfonic acid (PFEESA)
- Perfluoro-3-methoxypropanoic acid (PFMPA)
- Perfluoro-4-methoxybutanoic acid (PFMBA)
- Perfluorobutanoic acid (PFBA)
- Perfluorodecanoic acid (PFDA)
- Perfluorododecanoic acid (PFDoA)
- Perfluoroheptanesulfonic acid (PFHpS)
- Perfluoroheptanoic acid (PFHpA)
- Perfluorohexanoic acid (PFHxA)
- Perfluorononanoic acid (PFNA)
- Perfluoropentanesulfonic acid (PFPeS)
- Perfluoropentanoic acid (PFPeA)
- Perfluorotetradecanoic acid (PFTA)
- Perfluorotridecanoic acid (PFTrDA)
- Perfluoroundecanoic acid (PFUnA)
Cities ranked by the records
Ranked by the Purity Score of each city's main water system, highest first. Scores belong to water systems; there is no county score. The score is computed only from contaminants measured in the published EPA record, so this ranks the record, not which city's water is safest. How the score works.
0of 3 cities above the 15 µg/L action level
Based on each system's 90th-percentile result. Lead from household plumbing isn't in this record.
Lead in WisconsinLargest water systems
- West BendWEST BEND WATERWORKS · WI267012032,149 served
- GermantownGERMANTOWN WATER UTILITY · WI267010520,027 served
- HartfordHARTFORD WATERWORKS · WI267011015,805 served
Frequently asked
How does Washington County tap water compare across cities?
PurityMap ranks 3 cities in Washington County by the Purity Score of each city's main water system, computed only from contaminants measured in the published EPA record. Scores belong to water systems, not to cities. The highest published score is Germantown's main water system: GERMANTOWN WATER UTILITY · PWSID WI2670105 · Purity Score 95 (Excellent) · Confidence: moderate · Assessed at the water-system level. The ranking compares the records, not which city's water is safest, and your own tap can differ with household plumbing.
How many Washington County cities had a PFAS sample above a 2024 EPA limit?
2 of 3 Washington County city reports had a PFAS sample above a 2024 EPA limit in EPA's UCMR 5 testing, including Hartford (PFOA 6.8 ng/L), West Bend (PFOA 6.5 ng/L). That limit is judged on a yearly average, and water systems have until 2029 to meet it, so a single sample is not a violation. PFAS were detected at any level in 2.
Is there lead in Washington County tap water?
Utilities report lead as a 90th-percentile result from home taps. 3 of 3 Washington County cities reported a value above zero, and none was above the 15 µg/L federal action level. Lead usually comes from a building's own pipes and fixtures, so only a test at your tap tells you what you drink.
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